Rotary furnace



\ Aug. 16, 1927. 1,638,909

J. F. BAKER ROTARY FURNACE Filed July 27, 1926 2 Sheets-Sheet l FgZ.

WITNESSES:

INVENTOR ./'Eohn F50/(er.

RNY

Patented ug. 16, 1927.

UNITED STATES PATENT OFFICE.

JOHN F. BAKER,

IANUFACTURING COMPANY,

OF MANSFIELD, OHIO, ASSIGNOR TO WESTINGHOUSE ELECTRIC &

A CORPORATION OF PENNSYLVANIA.

ROTARY FURNACE.

Application llled July 27, 1926. Serial No. 125,143.

My invention relates to furnaces and particularly to rotary furnaces having means for automatically effecting the periodic discharge of heat-treated material therefrom.

An object of my invention is to provide an eiiicient discharge means for a furnace.

Another object of my invention is to provide in a furnace having a conveyor carrying pivoted hearth trays, and a rotatable l0 cam means for periodically and successively tilting said trays to cause the discharge of materlal therefrom.

Other objects of m parent from the disc osure.

In practicin my invention according to the present em odiment, a power-driven rotary conveyor having pivoted-hearth-trays thereon is provided in cooperative relation with a heat-treating furnace, similar to the rotary furnace shown in my co-pending application Serial No. 117937 filed June 23,

1926. A power-driven rotatable cam is provided for periodically and successively enaging the tra s to tilt them and effect the ischarge of eat-treated material therefrom. A means, similar to that shown in the above-mentioned application, is provided to control the o eration of the cam in accordance with t e movement of the conve or.

in the drawings, Fig. 1 is a vertical sectional view of a rotary furnace showing my cam tilting means 'operatively connected thereto.

Fig. 2 is a horizontal section of one half of the furnace.

Referring to the drawings, a preferabl annular rotar furnace 10 is provided wit an annular c amber 11 and has an outer casing 13 and inner wallsl of refractory insulatmg material 15. Suitable heating means are provided in said chamber, such heating means being here s hown as electric heating elements 18 that are electrically connected to a suitable source of energy (not shown).

An annular runway 20 is provided 1n the bottom portion of the furnace. The upper portion of the runway opens into the annuinvention will be aplar chamber 11.

An annular column 27 is vertically positioned in the runwa and is so supported on the rim 22of a w eel 23, asto be moved through the runway upon rotation of the supporting member.

wheel 23. The upper end of the annular column has a'hearth-supporting member 26 that may. be integral therewith. A hearth tray 27 is'mounted on each hearth-supporting member and is connected to the member by a ivoted joint, located at the outer edges of t e hearth tray and its supporting member, the inner edge of the tray being free and extending over the' edge of the The hearth tray is adapted to receive material to be heattreated.

Sealing means for the runway 2O are preferably provided at the bottom of the furnace and comprise concentric channel members 29 and 30 secured to the furnace near the runway and having such circular space between them as to ermit the passage of the columns 21 there etween. An inverted annular channel member 31 is secured to the columns and is adapted to be immersed in sand or other suitable material that -is placed in the channel members 29 and 30.

The wheel .23 is rotatably mounted on a .central bearing 32 and has its rim 22 resting on a plurality of roller members 33. For the purpose of driving the wheel 23 a circular rack 35 is secured to the wheel and meshes with a gear wheel 36 that is mounted on a shaft 37. The shaft 37 is rotatably mounted in a pair of journal members 38. A worm gear wheel 40 is also secured to the shaft 37 and meshes with a worm screw 41 that is operatively connected to a hearth motor 42 or other suitable prime mover. The hearth motor 42 is, of course, connected to` a suitable source of electrical energy.

A discharge outlet 44 is connected to the furnace and has its outer end immersed in oil or other quenchin medium in the tank 45. The outlet 44 is a apted to receive heattreated material that is discharged from the hearth trays.

An automatic means for effecting a discharge of material from the hearth tray comprises a cam 47 that is eccentrically secured toa shaft 48, mounted in a suitable bearing 49 in the furnace walls. The cam is normally in position shown in Fig. 1 and is so located in the chamber 11 opposite to the dischargle outlet 44 as to be in position to engage t e free end of a hearth tray 27 when the tray arrives opposite to the dis- 'Ill charge outlet 44. It will be seen that, when the tray is in this position and the cam 47 is rotating, the tray will be tilted about its pivoted joint to permit the material on the tray to be discharged through the outlet 44. A power driven means to rotate the cam 47 is provided and comprises a worm wheel 51 that is keyed to the shaft 48 and meshes with a worm screw 52 that is secured to a vertical shaft 54. The vertical shaft 54 is mounted in suitable bearing members 55 and 56. At the upper end of the shaft 54, a worm screw 58 is connected and is adapted to mesh witha worm wheel 59 that is secured to the shaft 60 of a tilting motor or other prime mover 6l, the tilting motor being electrically connected to a suitable source of energy.

Means are provided to so periodically energize the motor 61 as to effect the movement of the cam 47 when successive hearth trays arrive opposite the discharge outlet 44, to cause a tilting of the hearth tray. A convenient form of such means is the commutator member 64 that is similar to the commutator member described in my copending application above mentioned. The commutator member 64 is secured to the upper end of a shaft 65 that is mounted in bearings 66 and 67 and is so secured, at its lower end, to the hub of the wheel 23 that it will be rotated when the wheel rotates.

Commutator member 64 comprises a metallic annular member 69 that is suitably insulated from the shaft and is provided with a plurality of integral projections 70. The number of .these projections is the same as the number of hearth trays. 1insulating material 71 is provided between adjacent rojections and has its outer surface ush with the outer end of the projections 70. A. brush 72 is insulatedly mounted on the furnace structure above the commutator 64 and is in electrical engagement with the annular member 69 of the commutator member 64 .at all times. .A second brush member 7 4 is insulatedly mounted on the furnace structure and is adapted to engage the periphery of the commutator member 64. The brushes 72 and 74 are electrically connected to the tilting-motor circuit.

A1llrhen the hearth motor is started, it isapparent that it will cause the wheel 23 to rotate, and the columns `21 and hearth trays 27 will be caused to move in a circular path. The projections 70 are so positioned as to rst engage the brush 74 when the corresponding hearth travs arrive opposite the discharge outlet 44. l 'nen the brush 74 engages a Aprojection 70, the circuit` through the motor 6i will be closed, andthe motor @twill start and cause'the rotation of the cam 47. jThe cam 47 will, of course, tilt the hearth tray that is opposite the discharge outlet 44, as heretofore described, thus causing the discharge of heat treated material'from the hearth tray 27. -The continued rotation of the cam 47 will permit the tray 27 to return to its original position.

The projections 70 are of such width as to permit the energization of the motor 61 for only the length of time necessary to permit the cam `to return to its lowermost position as shown in Fig. 1. The cam may be made circular to prevent any interference with the passage of a hearth tray 27 thereover, even though the cam -47 does not return to its exact original position. Preferably, there is a slight clearance between the cam and a tray passing over it.

While, in this embodiment of my invention, the conveyor is adapted to move continuously, by suitable means, such as the control system shown in my above-mentioned copending application, intermittent operation of the hearth motor may be provided to permitalternate operation ofthe hearth motor and the tilting motor. It will, of course, be obvious, that my tilting mechanism may be applied to furnaces 1n which the conveying means is not rotary.

While I have shown and described, for purposes of illustration, a particular form of my invention, it may, of course, be-employed in other formsv from the spirit and scope thereof, as set forth in the appended claims.

l claim as my invention:

1. .ln a furnace, in combination, a conveyor, means for driving said conveyor, a hearth tray pivotally mounted on the conveyor, and rotatable means positioned below the normalA level of thehearth tray forengaging said tray to effect the discharge of material therefrom.

2. ln a furnace, in combination, a conveyor, means for continuously driving said conveyor, a hearth tra pivotally mounted on the conveyor, rotate. le means positioned. below the normal level of the hearth tray for periodically Vtilting said tray to effect the discharge of material therefrom, and means for controlling the operation of sai rotatable means.

3. ln a furnace, in` combination, a' conveyor, means for driving said conveyor, a plurality of hearth trays pivtally-mounted thereon, a rotatable cam positioned below the normal level of thev hearth trays and adapted to periodically and successively engage said trays totilt `the same and eiect the discharge of material therefrom, lpowerdriven means for operating the cam, and control means for periodically causing the operation of said power-driven means.

4. ln a furnace, in combination, a conveyor, means for driving said conveyor, a

vplurality of hearth trays'pivotally mounted thereon, 4a rotatable, cam positioned below the normal level of the hearth trays and without departing adaptedto periodically and succeively engage said trays to tilt the same to elect the discharge of material therefrom, powerdriven .means for operating thev cam, and 'I electric means controlled b said conveyor for periodically causing t e operation of said power-driven means, said electric means v being adapted to maintain said powerdriven means in operation for a predetermined interval of time.

In vtestimony whereof, I have hereunto subscribed my name this 13th day of July',

JOHN F. BAKER. 

